Safety Of “Watch And Wait” Strategy After Neoadjuvant Chemoradiotherapy For Rectal Cancer Patients With Clinical Complete Response: A Meta-analysis

Objective:The meta-analysis was performed to evaluate the safety of watch and wait strategies in patients with rectal cancer who achieved complete clinical response after neoadjuvant chemoradiation.Methods:PubMed,The Cochrane Library and Embase databases were searched for relevant literature data.Studies that achieved cCR after nCRT were divided into watch and wait group(W&W)and surgical treatment group(ST).Literatures were screened according to the proposed inclusion and exclusion criteria,and the quality of the final included literatures was evaluated.Use Revman 5.3 software tools for local recurrence or regrowth(LR),distant metastasis(DM or DM + LR),savage surgery after local recurrence or regrowth(SS)?cancer-related death(CRD),2 years,5 years disease free survival(DFS),2 years and 5 years overall survival(OS)index for metaanalysis.Results:A total of 10 literatures were included,and the quality evaluation was all medium-to-high quality literatures.There were 966 rectal cancer patients,417 in the W&W group and 549 in the ST group.The results of the meta-analysis showed that the local regrowth/recurrence(LR)rate of the watch and wait(W&W)group was higher than surgical treatment(ST)group(RR=4.44,95%ci =1.81~10.90,P=0.001),and there was no significant difference in the savage surgery after local regrowth(SS),2-year disease-free survival rate(2-DFS),2-year survival rate(2-OS),5-year disease-free survival rate(5-DFS),5-year survival rate(5-OSs),and tumor-related death(CRD)between the two groups.Conclusion:Watch and wait strategy is feasible for some patients,from the aspects of avoiding the complications of surgery,retain organs has great advantages,residual tumor and local recurrence risk is higher than surgery group,savage surgery rateabove 90%,but still more conservative and passive,for patients in the strategy into,diagnostic criteria,and evaluation of cCR,follow-up time and strategy,relapse after treatment,such as standardization strategy,at the same time,the future more retrospective and prospective studies are needed to implement this strategy and the safety of patients is verified.